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991.
Background: The gastric bypass operation has evolved since 1966 when it was first introduced. The purpose of this study was
to determine the present state of gastric bypass by consensus among the members of the American Society for Bariatric Surgery
(ASBS). Method: A questionnaire was sent to all members of the ASBS. Forty-three percent responded reporting over 41,200 cases.
Results: Results were analyzed by using χ2 tests with a null hypothesis. Surgeons agreed on several technical aspects, preferring a vertical to a horizontal stapleline;
estimating, rather than measuring, the pouch volume at an average of 22 cc. Few surgeons divide the short gastric vessels,
and only 25% of surgeons polled use a restrictive ring or band proximal to the gastroenterostomy. Most surgeons calibrate
the gastroenterostomy, reporting a preferred average diameter of 12.3 cm. There was no consensus regarding forming the gastroenterostomy,
58% preferring hand-sewn and 42% stapled anastomoses. There was no consensus regarding dividing the gastric pouch from the
bypassed stomach: Conclusion: The preferred gastric bypass is vertical, with the pouch estimated at 20-25 cc, and the gastroenterostomy
calibrated at 12 mm diameter. The short gastric vessels need not be divided, and restrictive bands or rings are not preferred.
This technique of gastric bypass should be used as the control procedure when modifications are tested in future trials. Randomized
prospective studies are suggested to probe the benefits of division of the stomach pouch from the bypassed stomach. 相似文献
992.
Z. Kapoula M. P. Bucci F. Lavigne-Tomps F. Zamfirescu 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,122(4):413-423
The saccadic system has been traditionally regarded as two-dimensional (horizontal, vertical) and basically conjugate in the
two eyes. However, saccades to disparate targets (e.g., targets in real three-dimensional space that are located in different
directions and at different distances) are naturally disconjugate. We report here that memory-guided saccades to a disparate
target flashed 1 s earlier become disconjugate following repeated trials. After 15 min of repetition, the disconjugacy persists
even when the target to be remembered is no longer disparate. This suggests fast memory-based learning. Learning, however,
fails to occur if, during the repetition trials, the memory delay is 2 s. These findings suggest that the saccadic system
has access to a 3D representation of targets and is gifted with 3D short-term memory and learning capacity.
Received: 7 July 1997 / Accepted: 25 May 1998 相似文献
993.
994.
J Moncada J Schachter G Bolan J Nathan M A Shafer A Clark J Schwebke W Stamm T Mroczkowski Z Seliborska 《Diagnostic microbiology and infectious disease》1992,15(8):663-668
A newly developed microwell enzyme immunosorbent assay (EIA) system by Syva Company (Palo Alto, CA) can detect Chlamydia trachomatis in < 3 hr. It uses a polyclonal antibody to chlamydial lipopolysaccharide and end points are determined with a spectrophotometer. Three clinical trial sites (University of California Medical Center, San Francisco, CA; University of Washington, Seattle, WA; and Louisiana State University Medical Center, New Orleans, LA), compared this EIA with tissue culture (TC) for identifying Chlamydia in urogenital specimens. Overall prevalence by TC was 10.4% (136 of 1306). When tests were compared with TC (using vials or microtiter plates and a fluorescent antibody stain), we found an EIA sensitivity of 93.4% (127 of 136) and a specificity of 98.1% (1148 of 1170). This EIA has a performance profile that is, at the very least, comparable with other nonculture methods for diagnosing genital tract infections with C. trachomatis. 相似文献
995.
Alex Y. Chang Z. Nora Tu Julia L. Smith Philip Bonomi Thomas J. Smith Peter H. Wiernik Ronald Blum 《Investigational new drugs》1995,13(2):137-141
Summary Fifty-five patients with metastatic non-small cell lung cancer (NSCLC) were entered into this phase II randomized study for evaluating three new agents: gallium nitrate, amonafide and teniposide. The patients had to have ECOG performance status 0 or 1, no prior chemotherapy, and adequate hematological, hepatic and renal functions. Forty-seven patients were eligible and evaluable. Fourteen were randomized to receive gallium nitrate, 18 to amonafide and 15 to teniposide. Seventy-four percent of eligible patients were male. The majority of patients (89%) had an ECOG performance status 1. ECOG grade 4 toxicity occurred twice in patients on gallium nitrate, seven times on amonafide and 18 times on teniposide. The cause of death was attributed to amonafide in one patient (from sepsis) and to teniposide in two patients (due to infection and leukopenia). There was no objective response in all the patients entered. The overall survival times ranged from 2 weeks to 156 weeks with a median of 23 weeks. There were no survival differences among the three treatment arms. We conclude that gallium nitrate, amonafide and teniposide are inactive in metastatic NSCLC and do not warrant any further testing in this disease.The contents of this study is solely the responsibility of the authors and does not necessarily represent the official views of the National Cancer Institute. 相似文献
996.
997.
CT and MR imaging findings in adults with cerebellar medulloblastoma: comparison with findings in children. 总被引:4,自引:0,他引:4
P M Bourgouin D Tampieri S Z Grahovac C Léger R Del Carpio D Melan?on 《AJR. American journal of roentgenology》1992,159(3):609-612
The goal of this study was to determine if certain imaging features suggest the diagnosis of cerebellar medulloblastoma in adults and to determine how often the classic CT appearance seen in children is present in adults. The study included 28 adult patients with proved cerebellar medulloblastoma. The tumor was located in the cerebellar vermis in 14 patients and in a cerebellar hemisphere in 14 patients. Thirteen patients had unenhanced CT of the brain, all patients had contrast-enhanced CT, and eight patients had unenhanced MR imaging. The imaging features in adults were compared with those in children, as described in the literature. In our adult patients, all tumors were hyperdense compared with gray matter on unenhanced CT and showed a slight to moderate increase in density after injection of contrast medium. Thirteen lesions had well-defined margins, and 15 had poorly defined margins. Low-density areas consistent with cystic and necrotic degeneration were detected in 23 (82%) of the 28 tumors. By comparison, in children, medulloblastoma usually originates in the vermis. As in adults, the mass is hyperdense on unenhanced CT, but enhances markedly and homogeneously after injection of contrast medium. Usually no evidence of cyst formation or necrosis is seen, and the tumor margins are well defined. This classic CT appearance of medulloblastoma in children was identified in only three (11%) of the 28 adult patients. Medulloblastoma has a variable MR appearance in both children and adults. On T2-weighted images, lesions are hypo-, iso-, or hyperintense compared with normal gray matter. The CT findings of medulloblastoma in adults usually differ from those of medulloblastoma in children. The tumor has a variable and nonspecific appearance in adults and should always be considered in the differential diagnosis of a mass in the posterior fossa. 相似文献
998.
M J Ahern MD FRACP M Wetherall BEd A Leslie MB BS R H James BSc P J Roberts-Thomson PhD FRACP G C Rennie BA BSc MA 《International journal of clinical practice》1992,46(4):229-233
The elderly (age >65 years) are more vulnerable to side-effects induced by non-steroidal anti-inflammatory drugs (NSAIDs). We therefore performed a double-blind comparative study of ketoprofen SR and sulindac in patients with active rheumatoid arthritis, 65 years of age or older. Sulindac was chosen because of its possible renal sparing effects, and ketoprofen SR because of its short half life and sustained release delivery system. Eighty patients were entered. More patients withdrew from the study due to side-effects in the sulindac group; both treatment groups had a high incidence of side-effects during this study and during previous exposure to other NSAIDs, demonstrating that the elderly are susceptible to side-effects from NSAIDs. 相似文献
999.
R Z Losev O A Tsarev A M Gur'ianov 《Grudnaia i serdechno-sosudistaia khirurgiia / Ministerstvo zdravookhraneniia SSSR [i] Vsesoiuznoe nauchnoe obshchestvo khirurgov》1992,(1-2):34-37
The work analyses the results of the multimodality treatment of 80 patients among whom 20 suffered from endarteritis obliterans and 60 from atherosclerosis obliterans of the lower limb vessels. In the process of complex treatment intravascular laser irradiation of blood (ILIB) was carried out by introducing the light guide into a peripheral vein. In 31 (73.8%) patients with decompensated circulatory disorders in the limbs, a course of ILIB produced a good clinical effect. A positive effect was encountered in 35 (92.1%) of patients with subcompensated circulatory disorders in the lower limbs. The clinical efficacy of ILIB is due to normalization of blood coagulative properties, increase of the fibrinolytic potential, improvement of hemorheology, and normalization of the lipoprotein ratio. 相似文献
1000.
The survival rate and elastic properties of the anterior abdominal skin flap in Sprague-Dawley rats were studied in three groups of animals. In group 1 where the flaps were supplied by a normal artery, arterial flaps (1A) had better survival rate and elastic properties than venous flaps (1B). In group 2, where the flaps were supplied by an artery with diminished perfusion pressure, the arterial flaps (2A) still had slightly better results than venous flaps (2B). However, in group 3 where the flaps were supplied by a vein, venous flaps (3B) had better results than arterial flaps (3A). 相似文献